Tuesday, December 3rd it is the 40th anniversary of the Pioneer 10 flyby of Jupiter (1973). Pioneer 10 was the first spacecraft to fly through the asteroid belt, the first to fly close to Jupiter and the first to cross Neptune's orbit on a course to leave our solar system.

Wednesday is also the 192nd anniversary of German astronomer Wilhelm Tempel's birth. Temple discovered several comets, including comet 9P/Tempel in 1867. Deep Impact and Stardust each conducted missions at this comet.

December 4th appears to be a busy day for space. Back in 1996, "a little rover that did" was launched from Earth to Mars. It's Pathfinder's 17th anniversary of launch -- the Sojourner rover more than earned her driving license.

Pathfinder was the first spacecraft to bounce on another planet and the Sojourner rover was the first wheeled rover to explore another planet other than the moon. Sojourner led the way for Spirit, Opportunity and Curiosity.

December 7th is the 18th anniversary of the Galileo probe's descent into Jupiter.

This probe was the first to sample the atmosphere of a gas planet. During its 58-minute life, the probe penetrated 200 km (124 miles) into Jupiter's violent atmosphere before it was crushed, melted and/or vaporized by the pressure and temperature of the atmosphere.

December 7th is also the 108th anniversary of the birth of astronomer Gerard Kuiper.

Kuiper predicted the existence of the Kuiper Belt in 1951. The Kuiper Belt is a doughnut-shaped ring, extending just beyond the orbit of Neptune from about 30 to 55 AU. New Horizons, the first mission to the Kuiper Belt and an object that resides there (Pluto), is scheduled to arrive in 2015.